A compact ultrasonic transducer for an ultrasonic surgical instrument includes a proximal casing defining a hollow interior and a piezoelectric rod array including a plurality of piezoelectric rods radially spaced-apart from one another and arranged in a longitudinally-oriented direction. The piezoelectric rod array is disposed within the hollow interior. The compact ultrasonic transducer further includes a distal horn including a distal connector configured to engage a waveguide. The distal horn is configured to engage the proximal casing to enclose the piezoelectric rod array within the hollow interior. An ultrasonic surgical instrument including the compact ultrasonic transducer is also provided.